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  <div class="section" id="module-uuid">
<span id="uuid-uuid-objects-according-to-rfc-4122"></span><h1>21.20. <a class="reference internal" href="#module-uuid" title="uuid: UUID objects (universally unique identifiers) according to RFC 4122"><code class="xref py py-mod docutils literal notranslate"><span class="pre">uuid</span></code></a> --- UUID objects according to <span class="target" id="index-0"></span><a class="rfc reference external" href="https://tools.ietf.org/html/rfc4122.html"><strong>RFC 4122</strong></a><a class="headerlink" href="#module-uuid" title="永久链接至标题">¶</a></h1>
<p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/3.6/Lib/uuid.py">Lib/uuid.py</a></p>
<hr class="docutils" />
<p>This module provides immutable <a class="reference internal" href="#uuid.UUID" title="uuid.UUID"><code class="xref py py-class docutils literal notranslate"><span class="pre">UUID</span></code></a> objects (the <a class="reference internal" href="#uuid.UUID" title="uuid.UUID"><code class="xref py py-class docutils literal notranslate"><span class="pre">UUID</span></code></a> class)
and the functions <a class="reference internal" href="#uuid.uuid1" title="uuid.uuid1"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid1()</span></code></a>, <a class="reference internal" href="#uuid.uuid3" title="uuid.uuid3"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid3()</span></code></a>, <a class="reference internal" href="#uuid.uuid4" title="uuid.uuid4"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid4()</span></code></a>, <a class="reference internal" href="#uuid.uuid5" title="uuid.uuid5"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid5()</span></code></a> for
generating version 1, 3, 4, and 5 UUIDs as specified in <span class="target" id="index-1"></span><a class="rfc reference external" href="https://tools.ietf.org/html/rfc4122.html"><strong>RFC 4122</strong></a>.</p>
<p>If all you want is a unique ID, you should probably call <a class="reference internal" href="#uuid.uuid1" title="uuid.uuid1"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid1()</span></code></a> or
<a class="reference internal" href="#uuid.uuid4" title="uuid.uuid4"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid4()</span></code></a>.  Note that <a class="reference internal" href="#uuid.uuid1" title="uuid.uuid1"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid1()</span></code></a> may compromise privacy since it creates
a UUID containing the computer's network address.  <a class="reference internal" href="#uuid.uuid4" title="uuid.uuid4"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid4()</span></code></a> creates a
random UUID.</p>
<dl class="class">
<dt id="uuid.UUID">
<em class="property">class </em><code class="descclassname">uuid.</code><code class="descname">UUID</code><span class="sig-paren">(</span><em>hex=None</em>, <em>bytes=None</em>, <em>bytes_le=None</em>, <em>fields=None</em>, <em>int=None</em>, <em>version=None</em><span class="sig-paren">)</span><a class="headerlink" href="#uuid.UUID" title="永久链接至目标">¶</a></dt>
<dd><p>Create a UUID from either a string of 32 hexadecimal digits, a string of 16
bytes in big-endian order as the <em>bytes</em> argument, a string of 16 bytes in
little-endian order as the <em>bytes_le</em> argument, a tuple of six integers
(32-bit <em>time_low</em>, 16-bit <em>time_mid</em>, 16-bit <em>time_hi_version</em>,
8-bit <em>clock_seq_hi_variant</em>, 8-bit <em>clock_seq_low</em>, 48-bit <em>node</em>) as the
<em>fields</em> argument, or a single 128-bit integer as the <em>int</em> argument.
When a string of hex digits is given, curly braces, hyphens,
and a URN prefix are all optional.  For example, these
expressions all yield the same UUID:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">UUID</span><span class="p">(</span><span class="s1">&#39;{12345678-1234-5678-1234-567812345678}&#39;</span><span class="p">)</span>
<span class="n">UUID</span><span class="p">(</span><span class="s1">&#39;12345678123456781234567812345678&#39;</span><span class="p">)</span>
<span class="n">UUID</span><span class="p">(</span><span class="s1">&#39;urn:uuid:12345678-1234-5678-1234-567812345678&#39;</span><span class="p">)</span>
<span class="n">UUID</span><span class="p">(</span><span class="nb">bytes</span><span class="o">=</span><span class="sa">b</span><span class="s1">&#39;</span><span class="se">\x12\x34\x56\x78</span><span class="s1">&#39;</span><span class="o">*</span><span class="mi">4</span><span class="p">)</span>
<span class="n">UUID</span><span class="p">(</span><span class="n">bytes_le</span><span class="o">=</span><span class="sa">b</span><span class="s1">&#39;</span><span class="se">\x78\x56\x34\x12\x34\x12\x78\x56</span><span class="s1">&#39;</span> <span class="o">+</span>
              <span class="sa">b</span><span class="s1">&#39;</span><span class="se">\x12\x34\x56\x78\x12\x34\x56\x78</span><span class="s1">&#39;</span><span class="p">)</span>
<span class="n">UUID</span><span class="p">(</span><span class="n">fields</span><span class="o">=</span><span class="p">(</span><span class="mh">0x12345678</span><span class="p">,</span> <span class="mh">0x1234</span><span class="p">,</span> <span class="mh">0x5678</span><span class="p">,</span> <span class="mh">0x12</span><span class="p">,</span> <span class="mh">0x34</span><span class="p">,</span> <span class="mh">0x567812345678</span><span class="p">))</span>
<span class="n">UUID</span><span class="p">(</span><span class="nb">int</span><span class="o">=</span><span class="mh">0x12345678123456781234567812345678</span><span class="p">)</span>
</pre></div>
</div>
<p>Exactly one of <em>hex</em>, <em>bytes</em>, <em>bytes_le</em>, <em>fields</em>, or <em>int</em> must be given.
The <em>version</em> argument is optional; if given, the resulting UUID will have its
variant and version number set according to <span class="target" id="index-2"></span><a class="rfc reference external" href="https://tools.ietf.org/html/rfc4122.html"><strong>RFC 4122</strong></a>, overriding bits in the
given <em>hex</em>, <em>bytes</em>, <em>bytes_le</em>, <em>fields</em>, or <em>int</em>.</p>
<p>Comparison of UUID objects are made by way of comparing their
<a class="reference internal" href="#uuid.UUID.int" title="uuid.UUID.int"><code class="xref py py-attr docutils literal notranslate"><span class="pre">UUID.int</span></code></a> attributes.  Comparison with a non-UUID object
raises a <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>.</p>
<p><code class="docutils literal notranslate"><span class="pre">str(uuid)</span></code> returns a string in the form
<code class="docutils literal notranslate"><span class="pre">12345678-1234-5678-1234-567812345678</span></code> where the 32 hexadecimal digits
represent the UUID.</p>
</dd></dl>

<p><a class="reference internal" href="#uuid.UUID" title="uuid.UUID"><code class="xref py py-class docutils literal notranslate"><span class="pre">UUID</span></code></a> instances have these read-only attributes:</p>
<dl class="attribute">
<dt id="uuid.UUID.bytes">
<code class="descclassname">UUID.</code><code class="descname">bytes</code><a class="headerlink" href="#uuid.UUID.bytes" title="永久链接至目标">¶</a></dt>
<dd><p>The UUID as a 16-byte string (containing the six integer fields in big-endian
byte order).</p>
</dd></dl>

<dl class="attribute">
<dt id="uuid.UUID.bytes_le">
<code class="descclassname">UUID.</code><code class="descname">bytes_le</code><a class="headerlink" href="#uuid.UUID.bytes_le" title="永久链接至目标">¶</a></dt>
<dd><p>The UUID as a 16-byte string (with <em>time_low</em>, <em>time_mid</em>, and <em>time_hi_version</em>
in little-endian byte order).</p>
</dd></dl>

<dl class="attribute">
<dt id="uuid.UUID.fields">
<code class="descclassname">UUID.</code><code class="descname">fields</code><a class="headerlink" href="#uuid.UUID.fields" title="永久链接至目标">¶</a></dt>
<dd><p>A tuple of the six integer fields of the UUID, which are also available as six
individual attributes and two derived attributes:</p>
<table border="1" class="docutils">
<colgroup>
<col width="49%" />
<col width="51%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Field</th>
<th class="head">Meaning</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">time_low</span></code></td>
<td>the first 32 bits of the UUID</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">time_mid</span></code></td>
<td>the next 16 bits of the UUID</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">time_hi_version</span></code></td>
<td>the next 16 bits of the UUID</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">clock_seq_hi_variant</span></code></td>
<td>the next 8 bits of the UUID</td>
</tr>
<tr class="row-even"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">clock_seq_low</span></code></td>
<td>the next 8 bits of the UUID</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">node</span></code></td>
<td>the last 48 bits of the UUID</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="time.html#module-time" title="time: Time access and conversions."><code class="xref py py-attr docutils literal notranslate"><span class="pre">time</span></code></a></td>
<td>the 60-bit timestamp</td>
</tr>
<tr class="row-odd"><td><code class="xref py py-attr docutils literal notranslate"><span class="pre">clock_seq</span></code></td>
<td>the 14-bit sequence number</td>
</tr>
</tbody>
</table>
</dd></dl>

<dl class="attribute">
<dt id="uuid.UUID.hex">
<code class="descclassname">UUID.</code><code class="descname">hex</code><a class="headerlink" href="#uuid.UUID.hex" title="永久链接至目标">¶</a></dt>
<dd><p>The UUID as a 32-character hexadecimal string.</p>
</dd></dl>

<dl class="attribute">
<dt id="uuid.UUID.int">
<code class="descclassname">UUID.</code><code class="descname">int</code><a class="headerlink" href="#uuid.UUID.int" title="永久链接至目标">¶</a></dt>
<dd><p>The UUID as a 128-bit integer.</p>
</dd></dl>

<dl class="attribute">
<dt id="uuid.UUID.urn">
<code class="descclassname">UUID.</code><code class="descname">urn</code><a class="headerlink" href="#uuid.UUID.urn" title="永久链接至目标">¶</a></dt>
<dd><p>The UUID as a URN as specified in <span class="target" id="index-3"></span><a class="rfc reference external" href="https://tools.ietf.org/html/rfc4122.html"><strong>RFC 4122</strong></a>.</p>
</dd></dl>

<dl class="attribute">
<dt id="uuid.UUID.variant">
<code class="descclassname">UUID.</code><code class="descname">variant</code><a class="headerlink" href="#uuid.UUID.variant" title="永久链接至目标">¶</a></dt>
<dd><p>The UUID variant, which determines the internal layout of the UUID. This will be
one of the constants <a class="reference internal" href="#uuid.RESERVED_NCS" title="uuid.RESERVED_NCS"><code class="xref py py-const docutils literal notranslate"><span class="pre">RESERVED_NCS</span></code></a>, <a class="reference internal" href="#uuid.RFC_4122" title="uuid.RFC_4122"><code class="xref py py-const docutils literal notranslate"><span class="pre">RFC_4122</span></code></a>,
<a class="reference internal" href="#uuid.RESERVED_MICROSOFT" title="uuid.RESERVED_MICROSOFT"><code class="xref py py-const docutils literal notranslate"><span class="pre">RESERVED_MICROSOFT</span></code></a>, or <a class="reference internal" href="#uuid.RESERVED_FUTURE" title="uuid.RESERVED_FUTURE"><code class="xref py py-const docutils literal notranslate"><span class="pre">RESERVED_FUTURE</span></code></a>.</p>
</dd></dl>

<dl class="attribute">
<dt id="uuid.UUID.version">
<code class="descclassname">UUID.</code><code class="descname">version</code><a class="headerlink" href="#uuid.UUID.version" title="永久链接至目标">¶</a></dt>
<dd><p>The UUID version number (1 through 5, meaningful only when the variant is
<a class="reference internal" href="#uuid.RFC_4122" title="uuid.RFC_4122"><code class="xref py py-const docutils literal notranslate"><span class="pre">RFC_4122</span></code></a>).</p>
</dd></dl>

<p>The <a class="reference internal" href="#module-uuid" title="uuid: UUID objects (universally unique identifiers) according to RFC 4122"><code class="xref py py-mod docutils literal notranslate"><span class="pre">uuid</span></code></a> module defines the following functions:</p>
<dl class="function">
<dt id="uuid.getnode">
<code class="descclassname">uuid.</code><code class="descname">getnode</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#uuid.getnode" title="永久链接至目标">¶</a></dt>
<dd><p>Get the hardware address as a 48-bit positive integer.  The first time this
runs, it may launch a separate program, which could be quite slow.  If all
attempts to obtain the hardware address fail, we choose a random 48-bit number
with its eighth bit set to 1 as recommended in <span class="target" id="index-4"></span><a class="rfc reference external" href="https://tools.ietf.org/html/rfc4122.html"><strong>RFC 4122</strong></a>.  &quot;Hardware address&quot;
means the MAC address of a network interface, and on a machine with multiple
network interfaces the MAC address of any one of them may be returned.</p>
</dd></dl>

<span class="target" id="index-5"></span><dl class="function">
<dt id="uuid.uuid1">
<code class="descclassname">uuid.</code><code class="descname">uuid1</code><span class="sig-paren">(</span><em>node=None</em>, <em>clock_seq=None</em><span class="sig-paren">)</span><a class="headerlink" href="#uuid.uuid1" title="永久链接至目标">¶</a></dt>
<dd><p>Generate a UUID from a host ID, sequence number, and the current time. If <em>node</em>
is not given, <a class="reference internal" href="#uuid.getnode" title="uuid.getnode"><code class="xref py py-func docutils literal notranslate"><span class="pre">getnode()</span></code></a> is used to obtain the hardware address. If
<em>clock_seq</em> is given, it is used as the sequence number; otherwise a random
14-bit sequence number is chosen.</p>
</dd></dl>

<span class="target" id="index-6"></span><dl class="function">
<dt id="uuid.uuid3">
<code class="descclassname">uuid.</code><code class="descname">uuid3</code><span class="sig-paren">(</span><em>namespace</em>, <em>name</em><span class="sig-paren">)</span><a class="headerlink" href="#uuid.uuid3" title="永久链接至目标">¶</a></dt>
<dd><p>Generate a UUID based on the MD5 hash of a namespace identifier (which is a
UUID) and a name (which is a string).</p>
</dd></dl>

<span class="target" id="index-7"></span><dl class="function">
<dt id="uuid.uuid4">
<code class="descclassname">uuid.</code><code class="descname">uuid4</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#uuid.uuid4" title="永久链接至目标">¶</a></dt>
<dd><p>Generate a random UUID.</p>
</dd></dl>

<span class="target" id="index-8"></span><dl class="function">
<dt id="uuid.uuid5">
<code class="descclassname">uuid.</code><code class="descname">uuid5</code><span class="sig-paren">(</span><em>namespace</em>, <em>name</em><span class="sig-paren">)</span><a class="headerlink" href="#uuid.uuid5" title="永久链接至目标">¶</a></dt>
<dd><p>Generate a UUID based on the SHA-1 hash of a namespace identifier (which is a
UUID) and a name (which is a string).</p>
</dd></dl>

<p id="index-9">The <a class="reference internal" href="#module-uuid" title="uuid: UUID objects (universally unique identifiers) according to RFC 4122"><code class="xref py py-mod docutils literal notranslate"><span class="pre">uuid</span></code></a> module defines the following namespace identifiers for use with
<a class="reference internal" href="#uuid.uuid3" title="uuid.uuid3"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid3()</span></code></a> or <a class="reference internal" href="#uuid.uuid5" title="uuid.uuid5"><code class="xref py py-func docutils literal notranslate"><span class="pre">uuid5()</span></code></a>.</p>
<dl class="data">
<dt id="uuid.NAMESPACE_DNS">
<code class="descclassname">uuid.</code><code class="descname">NAMESPACE_DNS</code><a class="headerlink" href="#uuid.NAMESPACE_DNS" title="永久链接至目标">¶</a></dt>
<dd><p>When this namespace is specified, the <em>name</em> string is a fully-qualified domain
name.</p>
</dd></dl>

<dl class="data">
<dt id="uuid.NAMESPACE_URL">
<code class="descclassname">uuid.</code><code class="descname">NAMESPACE_URL</code><a class="headerlink" href="#uuid.NAMESPACE_URL" title="永久链接至目标">¶</a></dt>
<dd><p>When this namespace is specified, the <em>name</em> string is a URL.</p>
</dd></dl>

<dl class="data">
<dt id="uuid.NAMESPACE_OID">
<code class="descclassname">uuid.</code><code class="descname">NAMESPACE_OID</code><a class="headerlink" href="#uuid.NAMESPACE_OID" title="永久链接至目标">¶</a></dt>
<dd><p>When this namespace is specified, the <em>name</em> string is an ISO OID.</p>
</dd></dl>

<dl class="data">
<dt id="uuid.NAMESPACE_X500">
<code class="descclassname">uuid.</code><code class="descname">NAMESPACE_X500</code><a class="headerlink" href="#uuid.NAMESPACE_X500" title="永久链接至目标">¶</a></dt>
<dd><p>When this namespace is specified, the <em>name</em> string is an X.500 DN in DER or a
text output format.</p>
</dd></dl>

<p>The <a class="reference internal" href="#module-uuid" title="uuid: UUID objects (universally unique identifiers) according to RFC 4122"><code class="xref py py-mod docutils literal notranslate"><span class="pre">uuid</span></code></a> module defines the following constants for the possible values
of the <code class="xref py py-attr docutils literal notranslate"><span class="pre">variant</span></code> attribute:</p>
<dl class="data">
<dt id="uuid.RESERVED_NCS">
<code class="descclassname">uuid.</code><code class="descname">RESERVED_NCS</code><a class="headerlink" href="#uuid.RESERVED_NCS" title="永久链接至目标">¶</a></dt>
<dd><p>Reserved for NCS compatibility.</p>
</dd></dl>

<dl class="data">
<dt id="uuid.RFC_4122">
<code class="descclassname">uuid.</code><code class="descname">RFC_4122</code><a class="headerlink" href="#uuid.RFC_4122" title="永久链接至目标">¶</a></dt>
<dd><p>Specifies the UUID layout given in <span class="target" id="index-10"></span><a class="rfc reference external" href="https://tools.ietf.org/html/rfc4122.html"><strong>RFC 4122</strong></a>.</p>
</dd></dl>

<dl class="data">
<dt id="uuid.RESERVED_MICROSOFT">
<code class="descclassname">uuid.</code><code class="descname">RESERVED_MICROSOFT</code><a class="headerlink" href="#uuid.RESERVED_MICROSOFT" title="永久链接至目标">¶</a></dt>
<dd><p>Reserved for Microsoft compatibility.</p>
</dd></dl>

<dl class="data">
<dt id="uuid.RESERVED_FUTURE">
<code class="descclassname">uuid.</code><code class="descname">RESERVED_FUTURE</code><a class="headerlink" href="#uuid.RESERVED_FUTURE" title="永久链接至目标">¶</a></dt>
<dd><p>Reserved for future definition.</p>
</dd></dl>

<div class="admonition seealso">
<p class="first admonition-title">参见</p>
<dl class="last docutils">
<dt><span class="target" id="index-11"></span><a class="rfc reference external" href="https://tools.ietf.org/html/rfc4122.html"><strong>RFC 4122</strong></a> - A Universally Unique IDentifier (UUID) URN Namespace</dt>
<dd>This specification defines a Uniform Resource Name namespace for UUIDs, the
internal format of UUIDs, and methods of generating UUIDs.</dd>
</dl>
</div>
<div class="section" id="example">
<span id="uuid-example"></span><h2>21.20.1. Example<a class="headerlink" href="#example" title="永久链接至标题">¶</a></h2>
<p>Here are some examples of typical usage of the <a class="reference internal" href="#module-uuid" title="uuid: UUID objects (universally unique identifiers) according to RFC 4122"><code class="xref py py-mod docutils literal notranslate"><span class="pre">uuid</span></code></a> module:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">uuid</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># make a UUID based on the host ID and current time</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">uuid</span><span class="o">.</span><span class="n">uuid1</span><span class="p">()</span>
<span class="go">UUID(&#39;a8098c1a-f86e-11da-bd1a-00112444be1e&#39;)</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># make a UUID using an MD5 hash of a namespace UUID and a name</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">uuid</span><span class="o">.</span><span class="n">uuid3</span><span class="p">(</span><span class="n">uuid</span><span class="o">.</span><span class="n">NAMESPACE_DNS</span><span class="p">,</span> <span class="s1">&#39;python.org&#39;</span><span class="p">)</span>
<span class="go">UUID(&#39;6fa459ea-ee8a-3ca4-894e-db77e160355e&#39;)</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># make a random UUID</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">uuid</span><span class="o">.</span><span class="n">uuid4</span><span class="p">()</span>
<span class="go">UUID(&#39;16fd2706-8baf-433b-82eb-8c7fada847da&#39;)</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># make a UUID using a SHA-1 hash of a namespace UUID and a name</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">uuid</span><span class="o">.</span><span class="n">uuid5</span><span class="p">(</span><span class="n">uuid</span><span class="o">.</span><span class="n">NAMESPACE_DNS</span><span class="p">,</span> <span class="s1">&#39;python.org&#39;</span><span class="p">)</span>
<span class="go">UUID(&#39;886313e1-3b8a-5372-9b90-0c9aee199e5d&#39;)</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># make a UUID from a string of hex digits (braces and hyphens ignored)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">x</span> <span class="o">=</span> <span class="n">uuid</span><span class="o">.</span><span class="n">UUID</span><span class="p">(</span><span class="s1">&#39;{00010203-0405-0607-0809-0a0b0c0d0e0f}&#39;</span><span class="p">)</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># convert a UUID to a string of hex digits in standard form</span>
<span class="gp">&gt;&gt;&gt; </span><span class="nb">str</span><span class="p">(</span><span class="n">x</span><span class="p">)</span>
<span class="go">&#39;00010203-0405-0607-0809-0a0b0c0d0e0f&#39;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># get the raw 16 bytes of the UUID</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">x</span><span class="o">.</span><span class="n">bytes</span>
<span class="go">b&#39;\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f&#39;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="c1"># make a UUID from a 16-byte string</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">uuid</span><span class="o">.</span><span class="n">UUID</span><span class="p">(</span><span class="nb">bytes</span><span class="o">=</span><span class="n">x</span><span class="o">.</span><span class="n">bytes</span><span class="p">)</span>
<span class="go">UUID(&#39;00010203-0405-0607-0809-0a0b0c0d0e0f&#39;)</span>
</pre></div>
</div>
</div>
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